Your idea to leap-frog over the power section of the Sansui makes sense in terms of getting more power output. If you are fixed on retaining the pre section of the Sansui- and that's fine- it does not make sense to get crazy in terms of price on a power amp. Today's budget power amps can likely better the power section of the Sansui in many ways. Your particular application does not require more than 100 watts so something from Emotiva would work very well at low entry price. Plus you can try it out for 30-days with the option to return it. I don't know the Dahlquist 16 but I do have experience with the well known 10. It is not a system that can take a lot of power yet (to me) it was a system that seemed to want a lot of power to open up. Unfortunately the woofer seemed to get bogged down in thermal compression when pushed hard and this went counter to getting some punch and dynamics out of the system. Anyway, point I am trying to make is that there is probably a very real limit to what kind of power is needed in your project. So, I would think 75 to 100 modern watts is about what you should look for.